1. Field of the Invention
The present invention relates to a pipe connection joint, and more particularly, to a pipe connection joint that includes a linear slant portion formed on a pipe joining hole of a flange and a pipe-expanded portion expandably formed on a pipe, which is joined to the pipe joining hole, along the linear slant portion, thereby providing a sufficient joining strength due to an increase of a contact area between the flange and the pipe, securing a firm fixation, preventing rotation of the pipe and guaranteeing communalization. In addition, the present invention relates to a pipe connection joint that is provided with an inwardly-curved surface portion of the pipe bent by micro R bending technology to minimize a bending distance to thereby allow an easy product design in a restricted space and further provided with a sealing member seating portion formed by the pipe-expanded portion of the pipe without needing additional process for seating of a sealing member to thereby minimize machining and reduce manufacturing expenses.
2. Background Art
In general, a refrigeration cycle for vehicles generally connects a compressor, a condenser, an expansion valve and an evaporator through refrigerant pipes in consecutive order to form a refrigerant circuit, such that the refrigeration cycle cools the inside of the vehicles through circulating refrigerant.
In this instance, in order to increase joining force between the refrigerant pipes and the above-mentioned components, pipe connection joints are mounted on end portions of the refrigerant pipes.
The pipe connection joints are used not only for joining the refrigerant pipes to the components in the refrigeration cycle but also for joining pipes to objects to be connected in overall industry.
Pipe connection joints according to prior arts are illustrated in FIGS. 1 and 2.
First, the pipe connection joint 10 illustrated in FIG. 1 includes a flange 11 formed through cutting work and a pipe connection portion 12 formed on a lower face of the flange 11 through cutting work.
Furthermore, the pipe connection joint 10 further includes a pipe 13 welded on a side of the flange 11 in such a way as to communicate with the pipe connection portion 12.
Accordingly, when the flange 11 is joined to a connection object 1 through a bolt 15, the pipe connection portion 12 of the flange 11 is connected to a passage 2 of the connection object 1.
As described above, the pipe 13 can be easily assembled to the connection object 1 via the pipe connection joint 10, and it prevents a leakage of fluid.
However, the pipe connection joint 10 needs expensive materials and additional welding and machining as the pipe 13 must be welded on the side of the flange 11, and hence, the overall cost of manufacturing increases.
Moreover, the pipe connection joint 10 according to another example illustrated in FIG. 2 includes a pipe 35 bent in an L-shape using micro R bending technology, a flange 30 having a pipe coupling hole 31 formed on a side of the flange 30 for inserting the pipe 35 thereinto, and an O-bead 36 molded on the pipe projecting from the other side of the flange 30, the O-bead 36 being seated on a groove 32 formed on the side of the flange 30.
Additionally, a seating hole 37 is formed on an end portion of the pipe 35 for seating an O-ring 38 thereon.
Accordingly, when the flange 30 is joined to the connection object 1 through a bolt 39, the pipe projecting from the flange 30 is connected to a passage 2 of the connection object 1, and a leakage can be prevented via the O-ring 38.
Furthermore, a pair of reinforcing ribs 33 projectingly formed on one side of the flange 30 in order to reinforce joining force between the flange 30 and the pipe 35. In other words, the reinforcing ribs 33 prevents rotation of the pipe 35 while supporting both sides of the pipe 35 to thereby increase the joining force between the flange 30 and the pipe 35.
Since the pipe 35 is bent through the micro R bending technology, the bent portion of the pipe 35 can be partially received in one side of the flange 30 to thereby reduce a bending distance L1. However, the prior art has a problem in that it is difficult to commonalize it due to the reinforcing ribs 33, which are additionally used in portions requiring high intensity (joining strength between the flange and the pipe), such as vehicle engines.
In other words, a mounting direction of the pipe 35 can be changed according to positions of components mounted inside an engine room of a vehicle, but the mounting direction (bending direction) of the pipe 35 on the flange 30 cannot be changed since the reinforcing ribs 33 support both sides of the pipe 35, and finally, various kinds of flanges 30 must be manufactured in correspondence with various mounting directions of the pipe 35, and hence, it is difficult to commonalize the pipe 35.
As described above, since the flange 30 includes a hole 34, on which an inwardly bent portion of the pipe 35 is seated, and the reinforcing ribs 33, different kinds of joint flanges must be designed according to a piping design of the pipe 35, and hence, it is difficult to commonalize it.
In addition, the flange 30 has the hole 34 on which the inwardly bent portion of the pipe 35 is seated and the groove 32 on which the O-bead 36 is seated, and thence, the number of processes and expenses are increased.
Furthermore, the hole 34 and the groove 32 respectively formed for seating the inwardly bent portion 34 and the O-bead thereon reduce the joining force between the pipe 35 and the flange 30 to thereby deteriorate fixing force of the pipe 35.